Parts List

VHF Amplifier Instruction Manual VT-3 132 - 174 MHz iii
TABLE OF CONTENTS
Page
1 GENERAL....................................................................................................................1-1
1.1 Introduction .......................................................................................................1-1
1.2 Performance Specification .................................................................................1-1
2 THEORY OF OPERATION.........................................................................................2-1
2.1 Amplifier Operation...........................................................................................2-1
2.2 Power Requirements ..........................................................................................2-1
2.3 RF Circuitry .......................................................................................................2-2
2.3.1 VT-3/150 Lowpass Filter .......................................................................2-2
2.4 Power Control Circuitry .....................................................................................2-2
2.5 Power Sensing Circuitry ....................................................................................2-3
2.5.1 Output Power Sense ..............................................................................2-3
2.5.2 VSWR Sense.........................................................................................2-3
2.5.3 VSWR Overload ....................................................................................2-4
3 VT-3/150 AMPLIFIER ALIGNMENT .........................................................................3-1
3.1 General..............................................................................................................3-1
3.2 Repair Note........................................................................................................3-1
3.3 Recommended Test Equipment List...................................................................3-1
3.4 Printed Circuitboard Numbering Convention .....................................................3-2
3.5 Standard Factory Settings and Jumper Configuration ........................................3-2
3.6 VT-3/150 Amplifier Alignment ..........................................................................3-2
3.6.1 General..................................................................................................3-2
3.6.2 VT-3/150 Amplifier Adjustment ............................................................3-3
3.6.2.1 General Set-Up..........................................................................3-3
3.6.2.2 Output Power Alarm (Forward Power)......................................3-4
3.6.2.3 Output Power.............................................................................3-5
3.6.2.4 Antenna VSWR Alarm (Reverse Power)...................................3-5
3.6.2.5 Antenna VSWR Overload ..........................................................3-6
3.6.2.6 Procedure Verification ...............................................................3-6
4 ILLUSTRATIONS AND SCHEMATIC DIAGRAMS................................................4-1
4.1 VT-3/150 VHF Amplifier Component Layout...................................................4-2
4.2 VT-3/150 VHF Amplifier Schematic Diagram...................................................4-3
4.3 VT-3/150 VHF Lowpass Filter Component Layout...........................................4-5
4.4 VT-3/150 VHF Lowpass Filter Schematic Diagram..........................................4-5